Dear community, I entered some equations related to chemical equilibrium. I entered the input once with an index to one of the variables ("a_1") and once without the indices (just "a"). The result produced by Wolfram Alpha is completely different. Here are the two inputs to the solver:

10^-2.16=bh/a, 10^-7.21=ch/b, 10^-12.32=dh/c, a+b+c+d=1, 10^-14=oh

and

10^-2.16=bh/a1, 10^-7.21=ch/b, 10^-12.32=dh/c, a1+b+c+d=1, 10^-14=oh

Furthermore the result changes everytime I add an index to another variable ("b_1" instead of "b",...). Does anybody know the reason and can point me towards a valid solution?

Thank you very much! Andreas

P.S.: My project is chemistry-related. I want to model the course of the concentrations of all species during the titration of phosphoric acid with sodium hydroxide. The Input above models the first step, where no sodium hydroxide.